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1.
Mar Drugs ; 20(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35323481

RESUMO

This study reports on the green and cost-efficient synthesis of gold nanoparticles from three different red algae extracts. The nanoparticles synthesized were fully characterized by UV-Vis spectroscopy, HRTEM, and Z-potential. Relevant components occurring in the extracts, such as polysaccharides or phenolic content, were assessed by analytical techniques such as spectrophotometric assays and liquid chromatography. Finally, the antioxidant, antitumoral, and anti-inflammatory potential of both the extracts and the gold nanoparticles synthesized were analyzed in order to determine a possible synergistic effect on the nanoparticles. The results obtained confirmed the obtainment of gold nanoparticles with significant potential as immunotherapeutic agents. The therapeutic potential of these nanoparticles could be higher than that of inert gold nanoparticles loaded with bioactive molecules since the former would allow for higher accumulation into the targeted tissue.


Assuntos
Antineoplásicos/administração & dosagem , Antioxidantes/administração & dosagem , Misturas Complexas/química , Ouro/administração & dosagem , Fatores Imunológicos/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Rodófitas/química , Antineoplásicos/química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Citocinas/metabolismo , Ouro/química , Humanos , Fatores Imunológicos/química , Nanopartículas Metálicas/química , Fenóis/análise , Fenóis/farmacologia , Polissacarídeos/análise , Polissacarídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
2.
Mar Drugs ; 21(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36662193

RESUMO

Cancer still poses a global threat, since a lot of tumors remain untreatable despite all the available chemotherapeutic drugs, whose side effects, it must also be noted, still raise concerns. The antitumoral properties of marine seaweeds make them a potential source of new, less toxic, and more active antitumoral agents. Furthermore, these natural extracts can be combined with nanotechnology to increase their efficacy and improve targeting. In this work, a Codium tomentosum (CT) aqueous extract was employed for the green synthesis of gold nanoparticles (Au@CT). The complete characterization of Au@CT was performed by UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Zeta potential, electron microscopy, X-ray powder diffraction (XRD), high-performance steric exclusion chromatography (HPSEC), and by the determination of their antioxidant capacity. The antiproliferative activity of Au@CT was then tested in hepatic (HEPG-2) and pancreatic (BxPC-3) cell lines. Their potential capacity as enhancers of gemcitabine, a drug frequently used to treat both types of tumors, was also tested. The activity of Au@CT was compared to the activity of the CT extract alone. A synergistic effect with gemcitabine was proven for HEPG-2. Our results showed that gold nanoparticles synthesized from seaweed extracts with antitumoral activity could be a good gemcitabine enhancer.


Assuntos
Clorófitas , Nanopartículas Metálicas , Neoplasias , Humanos , Gencitabina , Nanopartículas Metálicas/química , Ouro/farmacologia , Ouro/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Química Verde/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Eur J Clin Microbiol Infect Dis ; 40(10): 2185-2190, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33987803

RESUMO

Enteroviruses (EV) have been linked to lymphocytic meningitis and exanthems, but they may also be involved in acute gastroenteritis (AGE), a condition whose aetiological agent often remains unidentified. In this work 1214 samples from individuals with AGE were studied with the aim of establishing the incidence of EV. The samples were collected between September and December in three different years and subjected to real-time genomic amplification in order to determine the viral load (VL). Of the 1214 samples studied, infection by a single virus was found in 328 cases (27%) and coinfection in 69 (5.7%). While adenoviruses (AdV) were the most frequent (14.8% of total), EV were present in 126 (10.4%) of the individuals tested. Of the 126 EV-positive samples, this virus was found as a single infection and coinfection in 76 (6.3%) and 50 (4.1%) cases, respectively. VL for EV was 5.58±1.51 log copies/ml (range 3.73-9.69) in the former and 6.27±1.75 (range 3.73-10.5) (p=0.02) in the latter. EV were identified in 97 children under 5 (16.9%) and in 29 (4.5%) patients over 5. Patients less than 5 years showed a higher VL that those more than 5 years age [6.08±1.57 (range 3.82-9.69) vs. 5.07±1.53 (range 3.73-10.58); (p=0.002)]. There was a high incidence of EV in AGE patients, and they were more frequent in those under 5, where they were found to replicate more efficiently. These results therefore indicate that testing for EV should be included in the diagnosis of AGE.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/isolamento & purificação , Gastroenterite/virologia , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Enterovirus/classificação , Enterovirus/genética , Enterovirus/fisiologia , Infecções por Enterovirus/epidemiologia , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Genótipo , Humanos , Lactente , Masculino , Filogenia , Carga Viral
4.
Molecules ; 26(4)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672102

RESUMO

Macroalgae are sources of bioactive compounds that are interesting from both a chemical and a medical point of view. Although their use in biomedicine has increased significantly in recent years, tests conducted to date have been mostly related to species from temperate latitudes, with the potential application of Antarctic biodiversity being minor. The wide variety of algae species present on Antarctic coastal areas can be a source of new antioxidants. Bearing this in mind, the brown macroalgae Desmarestia antarctica (DA) and the red Iridaea cordata (IC) were selected for the preparation of aqueous extracts with the aim of analyzing their antioxidant activity. This analysis was performed by determining reducing power, total phenolic content, and 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity. Furthermore, both extracts were employed to synthesize gold and silver nanoparticles. The nanomaterials were fully characterized by means of UV-Visible spectroscopy, transmission electron microscopy, Z potential measurements, and Fourier transform infrared spectroscopy, which confirmed the formation of stable, spherical nanoparticles with mean diameters of 13.7 ± 3.1 and 17.5 ± 3.7 nm for Ag@DA and Ag@IC and 12.6 ± 1.9 and 12.3 ± 1.6 nm for Au@DA and Au@IC. Antioxidant assays were performed after the synthesis of the nanomaterials to evaluate their possible synergistic effect with the extracts. The results suggest that polysaccharides and proteins may play a key role in the process of reduction and stabilization. Finally, for the sake of comparison, the results obtained for the Antarctic macroalgae Desmarestia menziesii and Palmaria decipiens have also been considered in the present work.


Assuntos
Antioxidantes/farmacologia , Ouro/metabolismo , Nanopartículas Metálicas/química , Phaeophyceae/química , Rodófitas/química , Prata/metabolismo , Regiões Antárticas , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Ouro/química , Tamanho da Partícula , Picratos/antagonistas & inibidores , Prata/química
5.
Virol J ; 15(1): 41, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29510723

RESUMO

After publication of the article [1], it was brought to our attention that the author E. López-Díez is missing their second affiliation. The author would also like to indicate an affiliation to "Universidade de Vigo, Pontevedra, Spain".

6.
Virol J ; 14(1): 214, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-29110680

RESUMO

BACKGROUND: Human papillomavirus (HPV) bivalent and quadrivalent vaccines have been widely implemented in worldwide organized immunization programs. A nonavalent HPV vaccine is now available in several countries. The objective was to describe the fraction of squamous non-invasive high-grade cervical intraepithelial lesions attributable to genotypes targeted by bi-quadrivalent vaccines and by nonavalent vaccine according to age and diagnosis in women living in the city of Vigo (Galicia, Spain). METHODS: Cervical scrapings (2009-2014) of women with histological diagnosis of cervical intraepithelial neoplasia grade 2 (CIN2, n = 145) and grade 3-carcinoma in situ (CIN3-CIS, n = 244) were tested with Linear Array HPV Genotyping test (Roche diagnostics, Mannheim, Germany). Hierarchical estimation of the fraction attributable to HPV 16/18 or HPV 31/33/45/52/58 detected alone or in combination was calculated. Absolute additional fraction attributable to genotypes targeted by nonavalent vaccine compared to genotypes targeted by bi-quadrivalent vaccines was calculated as the increment of attributable cases with respect to all studied cases. Age group 1, 2 and 3 included women 18 to 34, 35-44 and ≥45 years old, respectively. EPIDAT 3.1 was used. RESULTS: Fraction attributable to genotypes targeted by bi-quadrivalent vaccines was 59% CIN2 vs. 69% CIN3-CIS (p < 0.001). It was 63/51/50% of CIN2 and 78/66/45% of CIN3-CIS in age group 1, 2, 3, respectively. Fraction attributable to genotypes targeted by nonavalent vaccine was 86% CIN2 and 86% CIN3-CIS. It was 87/91/75% of CIN2 and 90/86/76% of CIN3-CIS in age group 1, 2, 3, respectively. Fraction attributable to genotypes targeted by these vaccines tended to decrease as age increased (p-trend <0.05). Globally, absolute additional attributable fraction was 16%, 26% and 29% in age group 1, 2 and 3, respectively (p < 0.005). CONCLUSIONS: Absolute additional fraction of CIN2 and CIN3-CIS attributable to genotypes targeted by nonavalent vaccine was observed in women of any age, especially in those over 35 years old.


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/genética , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Fatores Etários , Idoso , DNA Viral/genética , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Papillomaviridae/imunologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Prevalência , Estudos Prospectivos , Espanha/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/prevenção & controle
7.
Br J Cancer ; 111(9): 1870-80, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25121955

RESUMO

BACKGROUND: There is growing evidence of the protective role of dietary intake of flavonoids and lignans on cancer, but the association with bladder cancer has not been thoroughly investigated in epidemiological studies. We evaluated the association between dietary intakes of total and subclasses of flavonoids and lignans and risk of bladder cancer and its main morphological type, urothelial cell carcinoma (UCC), within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. METHODS: A cohort of 477 312 men and women mostly aged 35-70 years, were recruited in 10 European countries. At baseline, dietary flavonoid and lignan intakes were estimated using centre-specific validated questionnaires and a food composition database based on the Phenol-Explorer, the UK Food Standards Agency and the US Department of Agriculture databases. RESULTS: During an average of 11 years of follow-up, 1575 new cases of primary bladder cancer were identified, of which 1425 were UCC (classified into aggressive (n=430) and non-aggressive (n=413) UCC). No association was found between total flavonoid intake and bladder cancer risk. Among flavonoid subclasses, significant inverse associations with bladder cancer risk were found for intakes of flavonol (hazard ratio comparing fifth with first quintile (HRQ5-Q1) 0.74, 95% confidence interval (CI): 0.61-0.91; P-trend=0.009) and lignans (HRQ5-Q1 0.78, 95% CI: 0.62-0.96; P-trend=0.046). Similar results were observed for overall UCC and aggressive UCC, but not for non-aggressive UCC. CONCLUSIONS: Our study suggests an inverse association between the dietary intakes of flavonols and lignans and risk of bladder cancer, particularly aggressive UCC.


Assuntos
Carcinoma in Situ/epidemiologia , Dieta , Flavonoides , Lignanas , Neoplasias da Bexiga Urinária/epidemiologia , Adulto , Idoso , Carcinoma in Situ/etiologia , Carcinoma in Situ/prevenção & controle , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Prognóstico , Estudos Prospectivos , Fatores de Risco , Neoplasias da Bexiga Urinária/etiologia , Neoplasias da Bexiga Urinária/prevenção & controle
8.
Ann Oncol ; 25(8): 1609-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24827130

RESUMO

BACKGROUND: Disturbances in one carbon metabolism may contribute to carcinogenesis by affecting methylation and synthesis of DNA. Choline and its oxidation product betaine are involved in this metabolism and can serve as alternative methyl group donors when folate status is low. PATIENTS AND METHODS: We conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), to investigate plasma concentrations of the methyl donors methionine, choline, betaine (trimethylglycine), and dimethylglycine (DMG) in relation to colorectal cancer (CRC) risk. Our study included 1367 incident CRC cases (965 colon and 402 rectum) and 2323 controls matched by gender, age group, and study center. Multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for CRC risk were estimated by conditional logistic regression, comparing the fifth to the first quintile of plasma concentrations. RESULTS: Overall, methionine (OR: 0.79, 95% CI: 0.63-0.99, P-trend = 0.05), choline (OR: 0.77, 95% CI: 0.60-0.99, P-trend = 0.07), and betaine (OR: 0.85, 95% CI: 0.66-1.09, P-trend = 0.06) concentrations were inversely associated with CRC risk of borderline significance. In participants with folate concentration below the median of 11.3 nmol/l, high betaine concentration was associated with reduced CRC risk (OR: 0.71, 95% CI: 0.50-1.00, P-trend = 0.02), which was not observed for those having a higher folate status. Among women, but not men, high choline concentration was associated with decreased CRC risk (OR: 0.62, 95% CI: 0.43-0.88, P-trend = 0.01). Plasma DMG was not associated with CRC risk. CONCLUSIONS: Individuals with high plasma concentrations of methionine, choline, and betaine may be at reduced risk of CRC.


Assuntos
Betaína/sangue , Colina/sangue , Neoplasias Colorretais/etiologia , Metionina/sangue , Estado Nutricional/fisiologia , Sarcosina/análogos & derivados , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais/sangue , Neoplasias Colorretais/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Sarcosina/sangue
9.
Ann Oncol ; 24(10): 2645-2651, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23857962

RESUMO

BACKGROUND: In 1994, acrylamide (AA) was classified as a probable human carcinogen by the International Agency for Research on Cancer. In 2002, AA was discovered at relatively high concentrations in some starchy, plant-based foods cooked at high temperatures. PATIENTS AND METHODS: A prospective analysis was conducted to evaluate the association between the dietary intake of AA and ductal adenocarcinoma of the exocrine pancreatic cancer (PC) risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort using Cox regression modeling. EPIC includes >500,000 men and women aged 35-75 at enrollment from 10 European countries. AA intake was estimated for each participant by combining questionnaire-based food consumption data with a harmonized AA database derived from the EU monitoring database of AA levels in foods, and evaluated in quintiles and continuously. RESULTS: After a mean follow-up of 11 years, 865 first incident adenocarcinomas of the exocrine pancreas were observed and included in the present analysis. At baseline, the mean dietary AA intake in EPIC was 26.22 µg/day. No overall association was found between continuous or quintiles of dietary AA intake and PC risk in EPIC (HR:0.95, 95%CI:0.89-1.01 per 10 µg/day). There was no effect measure modification by smoking status, sex, diabetes, alcohol intake or geographic region. However, there was an inverse association (HR: 0.73, 95% CI: 0.61-0.88 per 10 µg/day) between AA intake and PC risk in obese persons as defined using the body mass index (BMI, ≥ 30 kg/m(2)), but not when body fatness was defined using waist and hip circumference or their ratio. CONCLUSIONS: Dietary intake of AA was not associated with an increased risk of PC in the EPIC cohort.


Assuntos
Acrilamida/toxicidade , Carcinoma Ductal Pancreático/induzido quimicamente , Carcinoma Ductal Pancreático/epidemiologia , Dieta/efeitos adversos , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/epidemiologia , Adulto , Idoso , Índice de Massa Corporal , Estudos de Coortes , Ingestão de Alimentos , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Obesidade , Estudos Prospectivos , Risco , Fatores de Risco , Inquéritos e Questionários , Circunferência da Cintura
10.
Ultrasound Obstet Gynecol ; 40(3): 297-303, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22740299

RESUMO

OBJECTIVE: To assess cognitive outcomes and structural changes in the central nervous system, the latter using a novel approach to examine changes in neuronal integrity of the optic nerve, in children at 5-6½ years of age who were born small-for-gestational age (SGA) at term having shown normal umbilical artery (UA) Doppler. METHODS: We compared neuronal damage, cognitive deficits and visuospatial perception in two cohorts of infants, one born SGA (n = 40) and one born appropriate-for-gestational age (AGA) (n = 39) in weight. Neuronal damage was evaluated using optical coherence tomography (OCT) of the optic nerve. Cognitive deficits were assessed with the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) test. Visuospatial perception was evaluated with Rey-Osterreich Complex Figure (ROCF) tasks. RESULTS: Children from the SGA group had a significantly thinner average retinal nerve fiber layer (RNFL) compared with those from the AGA group (98.2 vs 104.5 µm, P = 0.012). Children from the SGA group exhibited impaired performance in copy tasks on the ROCF (3.27 vs 3.56, P = 0.036) and a higher rate of suboptimal WPPSI test performance intelligence quotient scores (15% vs 0%; P = 0.025) compared with those from the AGA group. CONCLUSION: Term infants with normal UA Doppler born SGA are at increased risk for cognitive deficits and axonal loss in the RNFL at the age of 5-6½ years.


Assuntos
Axônios/patologia , Sistema Nervoso Central/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Nervo Óptico/fisiopatologia , Tomografia de Coerência Óptica/métodos , Ultrassonografia Doppler/métodos , Artérias Umbilicais/diagnóstico por imagem , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Percepção , Ultrassonografia Pré-Natal
11.
Glob Health Promot ; 29(3): 207-217, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35343291

RESUMO

INTRODUCCIÓN: n promoción de la salud se ha detectado en los últimos años un incremento de investigaciones con enfoques teóricos basados en activos de salud. Pese a los estudios identificados, no se dispone de suficiente evidencia sobre los efectos que diferentes tipos de activos pueden tener en la calidad de vida y en la morbimortalidad de la población. OBJETIVO: analizar la relación entre los activos de salud disponibles con indicadores de morbilidad, mortalidad y calidad de vida de la población asturiana en el año 2018. METODOLOGÍA: diseño ecológico a partir de datos agregados municipales procedentes de los 78 municipios de Asturias (1.034.960 habitantes). Tras aplicar la definición de activos de salud como aquellas variables que pudieran redundar en una mejora de la salud y del bienestar de los individuos y de las comunidades, se seleccionaron 19 variables de activos agrupados en cuatro categorías: individuales, socioeconómicas, comunitarias e infraestructura. Una vez controladas las variables relacionadas con las características demográficas de la población, se analizó la asociación de los activos con las tasas de morbimortalidad y de calidad de vida. Se desarrollaron 5 modelos predictivos a partir de modelos de regresión lineal múltiple para las variables dependientes: calidad de vida, enfermedades crónicas, mortalidad por todas las causas, mortalidad por enfermedades cardiovasculares (ECV) y por cáncer. RESULTADOS: la disponibilidad de recursos sanitarios (beta = 0.474), coberturas sociales (beta = 0.305) y redes de apoyo social (beta = 0.225) constituyen los activos de salud con mayor peso explicativo en los resultados de salud de la población asturiana. Las variables incluidas en los modelos predictivos de calidad de vida (R2 = 0.650) y de mortalidad por ECV (R2 = 0.544) son las que mostraron una mayor capacidad explicativa. CONCLUSIONES: la inversión en recursos sociosanitarios y la mejora de redes de apoyo social impulsados desde el ámbito de la salud pública pueden producir importantes mejoras en la salud de la población asturiana.

12.
Int J Biol Macromol ; 206: 553-566, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35245577

RESUMO

The integral utilization of sustainable resources with versatile, efficient and cleaner processes is encouraged. Hydrothermal treatment with subcritical water is a chemical free, tunable and rapid technology providing enhanced yield compared to conventional extraction and was explored for the benign by design extraction and depolymerization of carrageenan from Chondrus crispus. Up to 90% of the seaweed was solubilized operating under nonisothermal regime during heating up to 200 °C and 75.5% crude carrageenan yield was attained at 140 °C. Crude carrageenan could not be precipitated by ethanol from the extracts produced at 180 °C and higher temperatures, but ultrafiltration (100 kDa) of the extract obtained at 160 °C provided comparable recovery yields and similar rheological features to those of the ethanol precipitated product. Operation at 140 °C was preferred based on the higher recovery yield of the biopolymer and the whole extract was suitable for the green synthesis of polycrystalline decahedral quasi-spherical gold nanoparticles with a mean size distribution of 8.4 nm and Z potential value of -40.2 mV. Alternatively, the crude carrageen fraction was used for the formulation of printable biopolymer based gels with suitable mechanical properties, including a relevant gel strength enhancement (about 10-fold) when compared with conventional procedures.


Assuntos
Chondrus , Nanopartículas Metálicas , Carragenina/química , Chondrus/química , Etanol , Ouro , Hidrogéis , Extratos Vegetais/química
13.
Inorg Chem ; 50(11): 4705-12, 2011 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-21520892

RESUMO

In the past few years three topics in nanoscience have received great attention: catalytic activity of gold nanoparticles (AuNPs), their electron transfer properties, and magnetism. Although these properties could have much in common no report on their synergism has been published. Here we present 10-nm gold nanoparticles conveniently capped with a mixed self-assembled monolayer containing bis(dithiocarbamato)copper(II) complexes, which dismutate superoxide radical with extremely high efficiency (IC(50) = 0.074 µM). This behavior is interpreted as the result of an electron transfer (ET) process between AuNP core and the analyte when associated to copper(II). The ET process involving a charged AuNP core was detected by EPR and UV-vis spectroscopy.


Assuntos
Cobre/química , Ouro/química , Nanopartículas Metálicas/química , Compostos Organometálicos/química , Superóxidos/química , Tiocarbamatos/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
14.
Mater Sci Eng C Mater Biol Appl ; 123: 111960, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812588

RESUMO

Over the last years, there has been an increasing trend towards the use of environmentally friendly processes to synthesize nanomaterials. In the case of nanomedicine, the use of bionanofactories with associated biological properties, such as seaweed, has emerged as a promising field of work due to the possibility they open for both the preservation of those properties in the nanomaterials synthesized and/or the reduction of their toxicity. In the present study, gold (Au@SP) and silver (Ag@SP) nanoparticles were synthesized using an aqueous extract of Saccorhiza polyschides (SP). Several techniques showed that the nanoparticles formed were spherical and stable, with mean diameters of 14 ± 2 nm for Au@SP and 15 ± 3 nm for Ag@SP. The composition of the biomolecules in the extract and the nanoparticles were also analyzed. The analyses performed indicate that the extract acts as a protective medium, with the particles embedded in it preventing aggregation and coalescence. Au@SP and Ag@SP showed superior immunostimulant and antiproliferative activity on immune and tumor cells, respectively, to that of the SP extract. Moreover, the nanoparticles were able to modulate the release of reactive oxygen species depending on the concentration. Hence, both nanoparticles have a significant therapeutic potential for the treatment of cancer or in immunostimulant therapy.


Assuntos
Nanopartículas Metálicas , Alga Marinha , Adjuvantes Imunológicos/farmacologia , Ouro , Extratos Vegetais/farmacologia , Prata
15.
Int J Biol Macromol ; 183: 1436-1449, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34023369

RESUMO

Carrageenan was extracted from Mastocarpus stellatus using hot water extraction under atmospheric and pressurized conditions. The influence of heating temperature during a non-isothermal heating profile up to temperatures in the range 70-190 °C was studied to evaluate the extraction yields and properties of the carrageenan fraction. Under the selected conditions (130 °C), extracted carrageenan (CMs) was used for the green synthesis of gold nanoparticles (AuNPs). After the optimization of the reaction conditions, the synthesized gold nanoparticles (Au@CMs) were characterized by UV-Vis spectroscopy, Z potential measurements, electron microscopy, and X-ray diffraction analysis, which confirmed the formation of spherical, polycrystalline, and negatively charged nanoparticles with a mean diameter of 14.3 ± 2.1 nm. The study conducted by scanning transmission electron microscopy, energy dispersive X-ray analysis and mapping confirmed the presence of carrageenan stabilizing AuNPs. Finally, Fourier transformed infrared spectroscopy was performed to analyze the functional groups of CMs involved in the reduction and stabilization of AuNPs. The selective cytotoxicity and the antioxidant activity of the Au@CMs were evaluated in different cell lines and compared to the CMs. Au@CMs showed an improved antioxidant capacity in cells under oxidative stress and the induction of apoptosis in a monocytic cell line, while no antitumor effect was observed in a lung endothelial cell line.


Assuntos
Carragenina/química , Ouro/química , Nanopartículas Metálicas/química , Antioxidantes/química , Análise de Fourier , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
16.
J Virol Methods ; 294: 114143, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33774075

RESUMO

The N501Y mutation in SARS-CoV-2 variants found in several strains from the UK, South Africa and Brazil has been linked to increased transmission. In order to discriminate N501Y variants quickly, a single nucleotide polymorphism (SNP) discrimination assay was designed and validated. It was then deployed prospectively in 757 nasopharyngeal swabs. Validation of the novel variant discrimination assay corroborated the results in all validation panel samples (n = 63) through sequencing. This novel variant discrimination assay was then deployed prospectively in 757 clinical nasopharyngeal swabs during the last week of January 2021. N501Y was found in 206 (27.4 %) of the samples: 94 (28.2 %) men and 112 (26.85 %) women (p = 0.73). The patients in whom it was identified had a mean age of 47.8 ± 25.8 (0-96) years, similar to that of patients without this variant: 51.7 ± 25.9 (0-104) years (p = 0.06). 501Y variant was confirmed in 34 samples by sequence method and 501 N wild type was confirmed in 67. This method is sensitive, specific, and simple to apply in any microbiology lab.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Mutação , Polimorfismo de Nucleotídeo Único , SARS-CoV-2/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/virologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Estudos Prospectivos , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/genética , Adulto Jovem
17.
Mater Sci Eng C Mater Biol Appl ; 97: 498-509, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678937

RESUMO

Marine bio-resources are being widely studied as an invaluable source of compounds with therapeutic applicability. In particular, macroalgae contain an extended variety of bioactive compounds with different structures and promising biological applications. In this work, Ulva lactuca L. (hereafter UL) was utilyzed for the synthesis of gold and silver nanoparticles. Full characterization by UV-Vis spectroscopy, TEM, HRTEM and STEM miscroscopies, Z Potential and FTIR spectroscopy was performed. The first time in the scientific literature, the composition of carbohydrates of UL extract and their changes observed after nanoparticles synthesis were explored in order to investigate their possible role in the biosynthetic process. The reducing power, total phenolic content and DPPH scavenging activity of UL extract, Au@UL and Ag@UL nanoparticles were determined. The effects of UL extract, Au@UL and Ag@UL were tested in vitro on the colon cancer cell lines HT-29 and Caco-2, on normal primary neonatal dermal fibroblast cell line PCS-201-010, as well as on normal colon cell line CCD-112CoN. Lastly, the apoptotic activity and cellular uptake evaluation was determined for Au@UL and Ag@UL.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Prata/química , Ulva/metabolismo , Antioxidantes/química , Apoptose/efeitos dos fármacos , Carboidratos/análise , Carboidratos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Humanos , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Transmissão , Fenóis/química , Extratos Vegetais/química , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Mater Chem B ; 7(30): 4677-4691, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31364682

RESUMO

This is the first study to report on the biocompatible and immunogenic properties of one-pot synthesised gold and silver nanoparticles (Au@UI and Ag@UI) using the macroalgae Ulva intestinalis (UI). The UI aqueous extract, Au@UI, and Ag@UI were obtained under sterile conditions and fully characterized by UV-vis spectroscopy, TEM, HRTEM, STEM and FTIR spectroscopy. Moreover, for the first time, the composition of carbohydrates in the UI extract has been reported along with the changes observed after nanoparticle synthesis by size exclusion chromatography, in order to investigate their possible role in the biosynthetic process. This study suggested that the polysaccharide fraction of the extract is involved in the formation and stabilization of the nanoparticles. The potential toxicity of the samples was evaluated using different cell lines and the hemocompatibility was tested in mouse erythrocytes. In addition, ROS production, complement activation and cytokine release were evaluated to determine the immunogenicity. The results showed that Au@UI and Ag@UI exhibit good biocompatibility and hemocompatibility, with the exception of Ag@UI nanoparticles at high concentration, which were hemolytic. The samples induced ROS release and complement activation, two key mechanisms in innate immunity. The samples also induced the release of cytokines from Th1 and Th2 profiles, and other cytokines implicated in the activation of the immune system. Au@UI and Ag@UI were biocompatible and preserved the immunostimulant properties of the UI extract. Hence, Au@UI and Ag@UI could be useful as adjuvants in vaccine development and promote a balanced Th1 and Th2 immune response mediated by ROS production, cytokine release and complement activation.


Assuntos
Adjuvantes Imunológicos/síntese química , Nanopartículas Metálicas/química , Ulva/química , Adjuvantes Imunológicos/farmacologia , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Clorófitas , Ativação do Complemento/efeitos dos fármacos , Citocinas/metabolismo , Ouro , Imunidade Inata/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Camundongos , Polissacarídeos/química , Espécies Reativas de Oxigênio/metabolismo , Prata , Células Th1/imunologia , Células Th2/imunologia
19.
Analyst ; 133(4): 444-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18365111

RESUMO

A simple procedure for the bio-conjugation of amphiphilic polymer-coated quantum dots with antibodies is described. The formed bio-conjugates are purified from an excess of free antibodies and of free nanoparticles by size-exclusion HPLC and then characterized by fluorescence emission and MALDI-TOFMS. The applicability of the approach is demonstrated for aflatoxin B1 detection.


Assuntos
Aflatoxina B1/análise , Anticorpos/isolamento & purificação , Imunofluorescência , Pontos Quânticos , Animais , Humanos , Nanopartículas , Polímeros , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
Clin Transl Oncol ; 20(11): 1448-1454, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29671222

RESUMO

PURPOSE: The prognostic value of Ki-67 in triple-negative breast cancer (TNBC) is yet unclear because the cut-off points employed differ widely and its predictive effect may vary according to age. The purpose of this study was to analyze the role of Ki-67 among patients with TNBC, and determine the optimal Ki-67 cut-off point to demonstrate its prognostic relevance associated with patient age and treatment strategy. METHODS/PATIENTS: 201 consecutive patients treated for primary TNBC from 1999 to 2014 were analyzed. Clinicopathological characteristics and outcomes were compared between patients treated with neoadjuvant or adjuvant chemotherapy. We used time-dependent receiver operating characteristic (ROC) curve and time-dependent area under the ROC curve (AUC) to evaluate the discriminative ability of Ki-67 at 3 and 5 years of follow-up. A Ki-67 cut-off point that maximized sensibility and specificity was established. Interaction effect between age and Ki-67 on disease-free survival (DFS) and overall survival (OS) was evaluated by stratified analysis. RESULTS: According to the coordinates of the ROC curves, the best cut-off point for Ki-67 was 60% (high/low). In the whole group, there was not a statistically significant association between Ki-67 and OS and DFS, using a cut-off point of 60%. In multivariate analysis (COX proportional hazards regression), for DFS high Ki-67 (> 60%) was a poor prognostic factor in patients > 40 years old and a better prognostic factor among the patients < 40 years old. CONCLUSION: Prognostic value of Ki-67 in TNBC, using a cut-off point of 60%, may vary depending on age.


Assuntos
Envelhecimento/fisiologia , Biomarcadores Tumorais/metabolismo , Antígeno Ki-67/metabolismo , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/mortalidade , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Biomarcadores Tumorais/análise , Quimioterapia Adjuvante/estatística & dados numéricos , Terapia Combinada/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Antígeno Ki-67/análise , Mastectomia/estatística & dados numéricos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/terapia
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